Pivoting battery carrier and a life safety device incorporating the same

ABSTRACT

An electronic device, for example a smoke alarm, that includes a battery carrier that includes a push to open and push to close apparatus for opening and closing the carrier. In one embodiment, the carrier is mounted so as to be pivotable between a closed position and an open position. Pivoting movement of the carrier is controlled by a double acting latch mechanism that includes at least one heart-shaped cam groove and at least one cam follower engaging with the cam groove. The carrier is a simple to access and operate to facilitate replacement of the battery. A lockout mechanism can also be provided to prevent closure of the carrier without a battery installed. In addition, a tamper resist mechanism can be provided to prevent the carrier from being opened when the carrier is at the closed position.

[0001] This application claims the benefit of provisional applicationSer. No. 60/453,319, filed Mar. 10, 2003, and which is incorporatedherein by reference.

FIELD OF THE INVENTION

[0002] The invention relates to electronic devices that utilize abattery carrier. More particularly, the invention relates to a batterycarrier for use with electronic devices, for example life safety devicesincluding but not limited to smoke alarms and carbon monoxide alarms,that utilize one or more batteries.

BACKGROUND OF THE INVENTION

[0003] Electronic devices that employ battery compartments for holdingone or more batteries are well known in the art. The batterycompartments on such devices need to be accessible to permit insertionof one or more batteries, as well as replacement of the batteries asneeded. U.S. Pat. Nos. 5,413,499 and 6,117,575 disclose pivoting batterycompartments for holding 9-volt batteries that purport to facilitatebattery installation into electronic devices.

[0004] In certain electronic devices it is especially important for abattery to be properly installed and for a depleted battery to bereplaced promptly by a fresh battery. An example of such a device is asmoke alarm. Many smoke alarms utilize one or more batteries, forexample a single 9-volt battery, as a back-up power source to poweroperation of the alarm in the event mains power is absent. If mainspower is interrupted, it is critical that the battery be present toensure continued and proper operation of the alarm. Due to the importantrole batteries play in many smoke alarm designs, there has been acontinuing effort in the industry to design smoke alarms to help ensurethat a battery is properly installed in the alarm and to provide anindication to a user when a battery is not installed or when a batteryneeds replacement.

[0005] There is a continuing need for electronic devices, for examplelife safety devices including smoke alarms, in which batteryinstallation is simplified and which are designed to help ensure that abattery is properly installed.

SUMMARY OF THE INVENTION

[0006] The invention relates to an electronic device that incorporatesat least one battery either as a primary power source or as a back-uppower source. The electronic device is constructed to facilitate batteryinstallation into the device, prevent improper installation of abattery, provide a visual indication that a battery has not beeninstalled, and to prevent unauthorized access to the battery.

[0007] The electronic device can be any device that utilizes at leastone battery. However, the inventive concepts disclosed herein areespecially beneficial for use with life safety devices, for examplesmoke alarms, carbon monoxide alarms, flame detectors, and other lifesafety alarms that detect a potential life threatening condition andprovide a warning alarm to warn of the possible life threateningcondition.

[0008] The electronic device preferably includes a pivoting batterycarrier that is configured to carry at least one battery, for example a9-volt battery. The battery carrier is mounted so as to be pivotablebetween a closed position, in which access to the battery is prevented,and an open position, in which the battery can be accessed. Pivotingmovement of the pivoting battery carrier is controlled by apush-to-open/push-to-close mechanism, preferably a double acting latchmechanism that includes at least one heart-shaped cam groove and atleast one cam follower engaging with the cam groove. The use of thistype of latch mechanism on a pivoting battery carrier provides a simplemethod of accessing the battery carrier to permit replacement of thebattery, and requires very little dexterity on the part of a user tooperate.

[0009] The electronic device can also include means, for examplestructure integral with the electronic device, to prevent closure of thebattery carrier from the open position if a battery is incorrectlyinstalled in the battery carrier.

[0010] When used on a life safety device, for example a smoke alarm, itis preferred that the pivoting battery carrier be mounted adjacent toand accessible from the bottom of the alarm housing. Therefore, when thealarm is mounted in place, for example on a ceiling, the battery carrieris accessible to and operable by the user from beneath the alarm,without requiring removal of any alarm components.

[0011] In some embodiments, a lockout mechanism is also provided that isconfigured to prevent closure of the battery carrier, when the batterycarrier is at the open position, without a battery installed in thebattery carrier.

[0012] In addition, a tamper resist mechanism can be provided that isconfigured to prevent the battery carrier from being opened when thebattery carrier is at the closed position.

[0013] In accordance with a first aspect of the invention, a life safetyalarm is provided that comprises an alarm housing that houses a systemto detect a life threatening condition and alarm electronics. The alarmalso includes a battery carrier that is configured to carry at least onebattery, with the battery carrier being pivotally connected to the alarmhousing for pivoting movement relative to the alarm housing between aclosed position and an open position.

[0014] In another aspect of the invention, a life safety alarm comprisesan alarm housing that houses a system to detect a life threateningcondition and alarm electronics. The alarm also includes a batterycarrier that is mounted adjacent to and accessible from the bottom ofthe alarm housing.

[0015] In another aspect of the invention, a life safety alarm comprisesan alarm housing that houses a system to detect a life threateningcondition and alarm electronics. The alarm also includes a batterycarrier that is configured to carry at least one battery, and thebattery carrier is connected to the alarm housing by a push-to-open andpush-to-close mechanism. The battery carrier is also connected to thealarm housing so as to moveable relative to the alarm housing between aclosed position and an open position

[0016] In yet another aspect of the invention, an electronic devicecomprises a housing that houses components necessary for the operationof the electronic device, and a battery carrier that is configured tocarry at least one battery. The battery carrier is connected to thehousing for movement relative to the housing between a closed positionand an open position. In addition, a latch mechanism connects thebattery carrier to the housing. The latch mechanism includes at leastone heart-shaped cam groove and at least one cam follower engaged in thecam groove to control the movements of the battery carrier between theopen and closed positions and to retain the battery carrier at theclosed position.

[0017] These and various other advantages and features of novelty whichcharacterize the invention are pointed out with particularity in theclaims annexed hereto and forming a part hereof. However, for a betterunderstanding of the invention, its advantages and objects obtained byits use, reference should be made to the drawings which form a furtherpart hereof, and to the accompanying description, in which there isdescribed a preferred embodiment of the invention.

DESCRIPTION OF THE DRAWINGS

[0018] These and other features of the invention will now be describedwith reference to the drawings of preferred embodiments, which areintended to illustrate and not to limit the invention and in which:

[0019]FIG. 1 is a view of a base of a smoke alarm that includes apivoting battery carrier according to the invention, as the smoke alarmwould appear to someone looking upward towards the smoke alarm when thesmoke alarm is mounted on a ceiling.

[0020]FIG. 2 is a view of the smoke alarm housing in the same directionas FIG. 1, with a cover of the alarm housing removed to show details ofthe interior of the alarm housing.

[0021]FIG. 3 is a side view of the battery carrier in a closed position.

[0022]FIG. 4 is a side view similar to FIG. 3, showing the batterycarrier pushed upward to initiate opening of the carrier.

[0023]FIG. 5 is a side view similar to FIG. 3, showing the batterycarrier at the open position.

[0024]FIG. 6 is a side view similar to FIG. 3, showing the batterycarrier being pushed back to the closed position.

[0025]FIG. 7 is a side view similar to FIG. 3, showing the batterycarrier at the open position with the battery removed to illustrate thelockout mechanism.

[0026]FIG. 8 is a side view similar to FIG. 3, showing the batterycarrier at the open position with the battery inserted to retract thelockout mechanism.

[0027]FIG. 9 is a view similar to FIG. 2 but with the battery carrierremoved to illustrate the tamper resist mechanism.

[0028]FIG. 10 is a perspective view of the alarm housing with the coverremoved and with a portion of the tamper resist mechanism removed toillustrate how the tamper resist mechanism is actuated.

[0029]FIG. 11A illustrates the tamper resist mechanism relative to thebattery carrier, with the tamper resist mechanism at an unlockedposition.

[0030]FIG. 11B illustrates the tamper resist mechanism at a lockedposition.

[0031]FIG. 12 is a view of an alternative embodiment of a smoke alarmemploying a battery carrier mounted for linear motion.

[0032]FIG. 13A is a cross-sectional view through line 13-13 of FIG. 12with the battery carrier in a closed position.

[0033]FIG. 13B is a cross-sectional view through line 13-13 of FIG. 12with the battery carrier in an open position.

DETAILED DESCRIPTION OF THE INVENTION

[0034] The invention relates to an electronic device that has a batterycarrier into which at least one battery is intended to be placed towholly or partially power the electronic device. Alternatively, the atleast one battery can function as a back-up power source in the event offailure of a primary power source connected to the electronic device.For convenience, the inventive concepts will be described herein withrespect to a life safety device, in particular a smoke alarm. However,it is to be realized that the inventive concepts could be appliedequally as well to other life safety devices, for example a carbonmonoxide alarm or a flame detector, and other electronic devices thatutilize at least one battery. In addition, for convenience, the smokealarm will be described herein as using a single 9-volt battery.However, it is to be realized that the inventive concepts describedherein could be utilized with other battery types and sizes, and withmore than one battery.

[0035] With reference to FIG. 1, a smoke alarm 10 having a batterycarrier 12 according to the invention is illustrated. The alarm 10includes an alarm housing 14 which in use will house the smoke detectionsystem and alarm electronics necessary for operation of the alarm 10.The specifics of the smoke detection system and the alarm electronicsare not necessary for a proper understanding of the inventive concepts.Suitable smoke detection systems and alarm electronics for use in thealarm 10, as well as the operation of a smoke alarm, would be known tothose of skill in the art having read this specification. In theillustrated embodiment, the alarm 10 is preferably powered by mainselectrical power, with a 9-volt battery 15 providing back-up power inthe event of interruption of mains power. However, the battery could bethe primary power source for the alarm 10 if desired.

[0036] The alarm housing 14 includes a base 16 and a cover 18 that isconnected to the base 16, as best seen in FIGS. 1, 9 and 10. Whenconnected to each other, the base 16 and the cover 18 enclose the smokedetection system and the alarm electronics. In use, the alarm housing 14will be detachably connected to a mounting plate 19 that is fixed to,for example, a ceiling in a building in which the alarm 10 is to beused. To achieve connection, the base 16 includes suitable attachmentstructure which, in the illustrated embodiment, comprises tabs 20 thatare circumferentially spaced around an upper end of the base 16, asshown in FIGS. 3-8. The tabs 20 engage with suitable structure, such asslots, on the mounting plate 19, with connection being achieved bybringing the alarm housing 14 and mounting plate 19 together and thenrotating the alarm housing 14 relative to the mounting plate to effectconnection. The use of tabs and slots to detachably connect an alarmhousing and a mounting plate upon rotation of the alarm housing relativeto the mounting plate is known to those of skill in the art.

[0037] Returning to FIG. 1, the battery carrier 12 is accessible fromthe bottom of the alarm housing 14 to permit insertion and replacementof the battery. The terms “upper”, “lower”, “bottom” and the like, asused herein, are in reference to the smoke alarm in use as it is mountedon a ceiling of a building. Therefore, the base 16 is generally closerto the ceiling than is the cover 18, and the cover is the portion of thealarm that, in use, will face downward toward the floor of the building.Because the battery carrier 12 is accessible from the bottom of thealarm housing 14, insertion and replacement of the battery is madeeasier and can be accomplished without disconnecting the alarm housingfrom the mounting plate as is required in many conventional smokealarms.

[0038] The battery carrier 12 will now be described with reference toFIGS. 2-11. The carrier 12 is a generally rectangular structure withopposed side walls 22, 24 (FIGS. 11A, 11B), an upper wall 26 extendingbetween the side walls 22, 24 (FIGS. 7, 11A, 11B), a rear wall 28 (FIG.7), a bottom wall 30 extending between the side walls 22, 24, and anopen end 31. The walls 22-30 define a battery cavity 32 that is sized toreceive the battery 15 through the open end 31 thereof with thenon-terminal end of the battery toward the rear wall 28.

[0039] The rear wall 28 includes a pivot shaft 34, the ends of which arerotatably supported by flanges 36, 38 of the base 16. The carrier 12fits within a rectangular cut-out in the cover 18 and is able to pivotrelative to the base 16 and the cover 18 between a closed position,shown in FIG. 3, and an open position, shown in FIG. 5. In the closedposition, the bottom wall 30 is generally flush with the surroundingportions of the cover 18, while in the open position, as shown in FIG.7, the open end 31 of the carrier 12 extends below the cover 18 topermit removal of a battery from and/or insertion of a battery into thecarrier 12. A spring 33, a portion of which is shown in FIG. 2, engagesthe upper wall 26 of the carrier 12 between the rear wall 28 and theopen end 31 for biasing the carrier 12 toward the open position.

[0040] A resilient detent 35, seen in FIGS. 5 and 7, is connected to thebottom wall 30 for retaining the battery 15 in the carrier 12. Thedetent 35 comprises a cantilevered arm connected at one end 37 to thebottom wall 30 and having an opposite, free end 39 having a raised lip.The lip includes an angled surface 40 which, as will be discussedfurther below, will initiate downward deflection of the free end 39during removal of the battery. As shown in FIG. 5, when the battery 15is installed, the lip on the end 39 prevents the battery 15 from fallingout of the carrier 12 when the carrier 12 pivots to the open position.Removal of the battery 15 is accomplished by lifting the terminal end ofthe battery upward and pulling the battery out. When the battery islifted upward, it engages the angled surface 40 thereby deflecting thefree end 39 downward to permit the battery to be pulled out of thecarrier 12.

[0041] The carrier 12 employs a double acting latch mechanism to controlthe pivoting movements of the carrier 12 between the open and closedpositions, and to retain the carrier at the closed position against thebiasing force of the spring 33. The latch mechanism is constructed sothat, starting from the closed position (FIG. 3), movement of thecarrier 12 to the open position is initiated by pushing upward on theend 42 of the carrier (FIG. 4) and then releasing. This releases thelatch mechanism and permits the carrier 12 to pivot to the open position(FIG. 5) under the biasing force of the spring 33. To close the carrier,the user again pushes upward on the end 42 (FIG. 6) until a click isheard, and then releasing. The click indicates that the latch mechanismhas engaged to retain the carrier at the closed position.

[0042] In the illustrated embodiment, the latch mechanism comprises aheart-shaped cam groove 44 defined on the outer facing surface of eachside wall 22, 24 of the carrier 12, and cam follower arms 46 that haveends that ride in the path of the cam groove 44. Only the cam groove 44in the side wall 22 is visible in the figures. It is to be understoodthat the cam groove in the side wall 24 is identical in construction tothe cam groove shown. Although the use of two cam grooves is described,a single cam groove could be used if desired.

[0043] Each cam groove 44 includes a latch position 48 at which the endsof the follower arms 46 reside when the carrier 12 is at the closedposition, as shown in FIG. 3. At this position, the carrier is latchedclosed until the ends of the follower arms are removed from the latchposition. Each cam groove 44 also includes an open position 50 at whichthe ends of the follower arms 46 reside when the carrier 12 is at theopen position, as shown in FIG. 5. At this position, the carrier is heldin the open position through the force of the spring 33, with thecontact between the follower arms and the cam groove preventing furtheropening of the carrier.

[0044] As shown in FIGS. 11A, 11B, the follower arms 46 are part of anintegral, U-shaped structure 52 that extends beneath the carrier 12 andis pivotally connected to the base 16 to permit the structure 52 withthe follower arms 46 to pivot as the ends of the follower arms followthe cam path, as shown in FIGS. 3-6. The follower arms 46 are preferablymade of a flexible material so that the ends thereof remain in contactwith the cam grooves 44 at all times as the follower arms travel overthe steps in the cam path.

[0045] The construction and operation of heart-shaped cam grooves iswell known, and further details are not described herein. See, forexample, U.S. Pat. No. 5,004,276. However, the operation will be brieflydiscussed with reference to FIGS. 3-6. From the closed position of thecarrier 12 shown in FIG. 3, where the ends of the follower arms are atthe latch position 48, the end 42 of the carrier is pushed upward asshown in FIG. 4. This causes the ends of the follower arms to leave thelatch position 48 and initiate clockwise travel of the follower arms inthe cam groove 44. When the pushing force is released, the carrier 12pivots open as shown in FIG. 5, with the follower arms travelingclockwise in the cam groove 44 to the open position. To close thecarrier, the end 42 is again pushed upward as shown in FIG. 6, with thefollower arms traveling clockwise on the opposite side of the camgroove. The end 42 is pushed upward until a click is heard, whichindicates that the ends of the follower arms have returned to the latchposition 48 to latch the carrier in the closed position.

[0046] Therefore, the carrier 12 with the double acting latch mechanismis intuitive to use, with the user simply pushing upward to open (i.e.push to open), and pushing upward again to close (i.e. push to close).

[0047] Turning to FIGS. 9 and 10, the alarm 10 is also constructed toprevent closure of the carrier 12 if the battery 15 is incorrectlyinstalled in the carrier 12. A battery terminal support 54 is connectedto the base 16 adjacent the open end 31 of the carrier 12. Terminals 56a, 56 b for engagement with the negative and positive terminals,respectively, on the battery 15 to connect the battery with the alarmelectronics are mounted on the support 54. A first pair of spaced walls58 a, 58 b are provided on the support 54 between which is the terminal56 a, and a second pair of spaced walls 60 a, 60 b are provided on thesupport 54 between which is the terminal 56 b.

[0048] The distance between the walls 58 a, 58 b is such as to permitthe negative terminal on the battery to fit therebetween to engage withthe terminal 56 a. Likewise, the distance between the walls 60 a, 60 bis such as to permit the positive terminal on the battery to fittherebetween to engage with the terminal 56 b. However, the distancebetween the walls 60 a, 60 b is less than the maximum diameter of thenegative battery terminal. As a result, the negative battery terminalcannot fit between the walls 60 a, 60 b.

[0049] Therefore, the battery is properly inserted into the carrier 12with the negative battery terminal to the left of the positive batteryterminal (when viewing FIG. 9), so that the negative battery engages theterminal 56 a and the positive battery terminal engages the terminal 56b. If the battery is incorrectly inserted into the carrier 12 with thenegative battery terminal to the right of the positive battery terminal(when viewing FIG. 9), closure of the carrier 12 is prevented due tointerference between the negative battery terminal and the walls 60 a,60 b.

[0050] An additional feature of the invention is that when the carrier12 pivots open, the terminals 56 a, 56 b are not readily exposed to auser trying to replace the battery. Some smoke alarms use switches toconnect and disconnect the terminals when the battery is changed, due tothe fact that there could be 120V on the terminals in some instances.However, switches are problematic and inherently unreliable. The carrier12, when it pivots open and the battery is removed, obstructs the pathto the terminals 56 a, 56 b. Therefore, the need to switch the terminals56 a, 56 b on and off when the battery is changed is eliminated.

[0051] The alarm 10 also includes a lockout mechanism that preventsclosure of the carrier 12 without the battery installed in the carrier.The provision of a lockout mechanism is important in smoke alarms andother life safety devices, because these devices often do not functionproperly without the appropriate battery installed. Further, the opencarrier provides a visual indication to the user of the alarm that thebattery is not installed and the device may not be functioning properly.

[0052] Referring to FIGS. 7 and 8, the lockout mechanism comprises alockout plate 70 that is slidably mounted along the top surface of theupper wall 26 of the carrier 12. The plate 70 is biased to a position inwhich the front end thereof projects beyond the front edge of the upperwall 26, as shown in FIG. 7, by a coil spring 72. One end of the spring72 is fixed to the plate 70, and the opposite end of the spring isconnected to a protrusion 74 that is fixed to and extends upward fromthe upper wall 26. The plate 70 also includes a raised arcuate portion76 that at least partially houses the spring 72, and the rear end of theplate includes a tab 78 integral therewith that projects downwardly intothe rear of the battery cavity 32.

[0053] In operation of the lockout mechanism, when no battery ispresent, the plate 70, including the tab 78 integral therewith, arebiased forwardly by the spring 72 as shown in FIG. 7. At this position,the front end of the plate 70 projects past the front edge of the upperwall 26. As a result, when the user tries to close the carrier 12, thefront end of the plate 70 engages the walls 58 a, 58 b, 60 a, and 60 bof the support 54 thereby preventing closure of the carrier 12. Thus,the walls of the support 54 act as a mechanical stop to prevent closureof the carrier. When a battery is installed into the battery cavity asshown in FIG. 8, the rear or non-terminal end of the battery forces thetab 78 and the plate 70 backward against the bias force of the spring72. This retracts the plate 70 so that the front end thereof no longerprojects beyond the front edge of the upper wall 26, and the carrier 12can be pivoted closed without interference from the walls 58 a, 58 b, 60a, and 60 b of the support 54.

[0054] The biasing force of the spring 72 acting on the rear of thebattery via the tab 74 also biases the battery toward the support 54 toprovide reliable contact force between the battery terminals and theterminals 56 a, 56 b when the carrier 12 is closed.

[0055] Turning to FIGS. 9-11, the alarm 10 also includes a tamper resistmechanism to prevent the carrier 12 from being opened. This preventstampering with, and unauthorized removal of, the battery from the alarm10. As previously described herein, the carrier 12 employs a latchmechanism that includes heart-shaped cam grooves on the carrier and camfollowers traveling in the cam grooves. One way to prevent opening ofthe carrier 12 employing such a latch mechanism is to prevent initiationof the opening movement of the carrier by preventing the carrier frombeing pushed upward to release the cam followers from the latch position48.

[0056] With reference to FIG. 9, the tamper resist mechanism includes aslide 90 that is slidably disposed on the downward facing surface of thebase 16. The slide 90 includes a pair of resilient fingers 92 a, 92 b,each of which includes a protuberance 94 a, 94 b at the free endthereof. A pair of rails 96 a, 96 b are fixed to the downward facingsurface of the base 16. The rails 96 a, 96 b face each other and eachrail includes a pair of spaced notches 98 that are adapted to receivethe protuberances 94 a, 94 b.

[0057] The slide 90 is constructed to slide back and forth relative tothe base 16 within the limit of the notches 98. In FIG. 9, the slide 90is shown at a “locked” position, with the protuberances 94 a, 94 bdisposed within a first set of the notches 98. The shape of theprotuberances 94 a, 94 b and notches 98 are such as to permit the slide90 to be actuated to the left, as shown by the arrow in FIG. 9, byapplying a sufficient force to the slide to force the protuberances 94a, 94 b from the first set of notches until the protuberances 94 a, 94 bengage with the second set of notches 98. At this position, the slide 90is at an “unlocked” position. Guides 100, 102 connected to the base 16help guide the slide 90 as it moves between the “locked” and “unlocked”positions. The ends of the rails 96 a, 96 b are preferably configured toprevent overtravel of the slide 90 beyond the “locked” position andbeyond the “unlocked” position.

[0058] The slide 90 also includes a block 104 that is integraltherewith. In addition, the carrier 12 includes a block 106 that isconnected to and projects upwardly from the upper wall 26. Asillustrated in FIG. 11A, at the “unlocked” position of the slide 90, theblock 104 is retracted to the right (when viewing FIG. 1A), and thecarrier 12 can be pushed upward to initiate opening of the carrier.However, as illustrated in FIG. 11B, when the slide 90 is at the“locked” position of FIG. 9, the block 104 is disposed above the carrier12 immediately above the block 106. As a result, the carrier 12 cannotbe pushed upward due to engagement between the blocks 104, 106, and thecarrier cannot be opened until the block 104 is retracted by sliding theslide 90 to the “unlocked” position.

[0059] Actuation of the slide 90 is achieved by using an object, such asthe end of a pen or a screwdriver, to move the slide 90. With referenceto FIG. 10, the slide 90 has been removed to show a slot 108 that isformed through the base 16. To access the slot 108, the alarm housing 14is first detached from the mounting plate 19. The end of the object isthen inserted through the slot 108 from the side of the base 16 oppositeto that shown in FIG. 10 to engage the top side of the slide 90. Theobject can then be used to actuate the slide between the “locked” and“unlocked” positions. The top side of the slide 90 preferably includes anotch or slot into which the end of the object can be inserted tofacilitate actuation of the slide by the object.

[0060] With this tamper resist mechanism, there are no loose parts thatcan be lost, as with many conventional tamper resist mechanisms.Further, the tamper resist mechanism is internal to the alarm housing14, which makes it difficult to tamper with or damage the mechanismparts.

[0061] The concepts disclosed herein can also be utilized on a batterycarrier that is mounted for linear motion. In such a case, the batterycarrier would be accessible from the bottom of the alarm housing andwould be mounted for linear movement between a first, closed positionwithin the alarm housing and a second, open position extending below thecover to permit removal of a battery and/or insertion of a battery intothe carrier. In this embodiment, the heart-shaped cam groove(s) would bearranged such that the axis thereof (i.e. a straight line connecting thelatch position and the open position of the cam groove) would beparallel to the direction of linear movement of the carrier. To open thecarrier, the user would push upward on the carrier, which would causethe carrier to extend beneath the alarm housing. To close the carrier,the user would again push upward on the carrier until a click is heard,to return the carrier to the closed position. As a result, like thepivoting carrier 12, the linearly mounted carrier would be apush-to-open and push-to-close arrangement.

[0062] An example of a battery carrier 112 that is mounted for linearmotion relative to an alarm housing 114 is illustrated in FIGS. 12, 13Aand 13B. The housing 114 is shown with its base 116. As shown in FIG.13A, where the carrier 112 is in its closed position, pushing upward onthe carrier 112 in the direction of the arrow initiates opening. FIG.13B illustrates the carrier 112 in its open position, and by pushingupward in the direction of the arrow, closing of the carrier 112 isinitiated. A pair of cam grooves 144 (only one cam groove is visible inthe figures) are formed centrally on the carrier 112, and cam followerarms 146 engage with the cam grooves 144.

[0063] The embodiments of the inventions disclosed herein have beendiscussed for the purpose of familiarizing the reader with novel aspectsof the invention. Although preferred embodiments have been shown anddescribed, many changes, modifications, and substitutions may be made byone having skill in the art without necessarily departing from thespirit and scope of the invention.

What is claimed is:
 1. A life safety alarm, comprising: an alarm housingthat houses a system to detect a life threatening condition and alarmelectronics; and a battery carrier configured to carry at least onebattery, the battery carrier is pivotally connected to the alarm housingfor pivoting movement relative to the alarm housing between a closedposition and an open position.
 2. The life safety alarm of claim 1,wherein the detection system comprises a smoke detection system.
 3. Thelife safety alarm of claim 1, comprising a double acting latch mechanismconnecting the battery carrier to the alarm housing, the latch mechanismconfigured to control pivoting movement of the battery carrier betweenthe closed and open positions.
 4. The life safety alarm of claim 3,wherein the double acting latch mechanism comprises at least one heartshaped cam groove, and a cam follower engaged with the cam groove. 5.The life safety alarm of claim 4, wherein the heart shaped cam groove isdefined on the battery carrier and the cam follower is attached to thealarm housing.
 6. The life safety alarm of claim 3, comprising a springengaged with the battery carrier that biases the battery carrier towardthe open position.
 7. The life safety alarm of claim 1, furthercomprising structure connected to the alarm housing that is configuredto prevent closure of the battery carrier from the open position if abattery is incorrectly installed in the battery carrier.
 8. The lifesafety alarm of claim 1, further comprising a lockout mechanism that isconfigured to prevent closure of the battery carrier, when the batterycarrier is at the open position, without a battery installed in thebattery carrier.
 9. The life safety alarm of claim 1, further comprisinga tamper resist mechanism that is configured to prevent the batterycarrier from being opened when the battery carrier is at the closedposition.
 10. A life safety alarm, comprising: an alarm housing thathouses a system to detect a life threatening condition and alarmelectronics; and a battery carrier that is mounted adjacent on the alarmhousing so that it is accessible from the bottom of the alarm housing,the battery being mounted for movement between a closed position and anopen position.
 11. The life safety alarm of claim 10, wherein thedetection system comprises a smoke detection system.
 12. The life safetyalarm of claim 10, further comprising a double acting latch mechanismconnecting the battery carrier to the alarm housing, the latch mechanismconfigured to control movement of the battery carrier between the closedand open positions.
 13. The life safety alarm of claim 12, wherein thebattery carrier is pivotally connected to the alarm housing for pivotingmovement relative to the alarm housing between the closed position andthe open position.
 14. The life safety alarm of claim 12, wherein thedouble acting latch mechanism comprises at least one heart shaped camgroove, and a cam follower engaged with the cam groove.
 15. The lifesafety alarm of claim 14, wherein the heart shaped cam groove is definedon the battery carrier and the cam follower is attached to the alarmhousing.
 16. The life safety alarm of claim 12, comprising a springengaged with the battery carrier that biases the battery carrier towardthe open position.
 17. The life safety alarm of claim 10, furthercomprising structure connected to the alarm housing that is configuredto prevent closure of the battery carrier from the open position if abattery is incorrectly installed in the battery carrier.
 18. The lifesafety alarm of claim 10, further comprising a lockout mechanism that isconfigured to prevent closure of the battery carrier, when the batterycarrier is at the open position, without a battery installed in thebattery carrier.
 19. The life safety alarm of claim 10, furthercomprising a tamper resist mechanism that is configured to prevent thebattery carrier from being opened when the battery carrier is at theclosed position.
 20. A life safety alarm, comprising: an alarm housingthat houses a system to detect a life threatening condition and alarmelectronics; and a battery carrier configured to carry at least onebattery, the battery carrier is connected to the alarm housing by apush-to-open and push-to-close mechanism, and where the battery carrieris connected to the alarm housing so as to moveable relative to thealarm housing between a closed position and an open position.
 21. Thelife safety alarm of claim 20, wherein the detection system comprises asmoke detection system.
 22. The life safety alarm of claim 20, whereinthe push-to-open and push-to-close mechanism comprises a double actinglatch mechanism connecting the battery carrier to the alarm housing. 23.The life safety alarm of claim 22, wherein the double acting latchmechanism comprises at least one heart shaped cam groove, and a camfollower engaged with the cam groove.
 24. The life safety alarm of claim23, wherein the heart shaped cam groove is defined on the batterycarrier and the cam follower is attached to the alarm housing.
 25. Thelife safety alarm of claim 20, comprising a spring engaged with thebattery carrier that biases the battery carrier toward the openposition.
 26. The life safety alarm of claim 20, further comprisingstructure connected to the alarm housing that is configured to preventclosure of the battery carrier from the open position if a battery isincorrectly installed in the battery carrier.
 27. The life safety alarmof claim 20, further comprising a lockout mechanism that is configuredto prevent closure of the battery carrier, when the battery carrier isat the open position, without a battery installed in the batterycarrier.
 28. The life safety alarm of claim 20, further comprising atamper resist mechanism that is configured to prevent the batterycarrier from being opened when the battery carrier is at the closedposition.
 29. An electronic device, comprising: a housing that housescomponents necessary for the operation of the electronic device; abattery carrier configured to carry at least one battery, the batterycarrier is connected to the housing for movement relative to the housingbetween a closed position and an open position; and a latch mechanismconnecting the battery carrier to the housing, the latch mechanismincludes at least one heart-shaped cam groove and at least one camfollower engaged in the cam groove to control the movements of thebattery carrier between the open and closed positions, and to retain thebattery carrier at the closed position.
 30. The electronic device ofclaim 29, wherein the electronic device is a life safety alarm, and thecomponents housed in the housing comprise a system to detect a lifethreatening condition and alarm electronics.
 31. The electronic deviceof claim 30, wherein the detection system comprises a smoke detectionsystem.
 32. The electronic device of claim 29, wherein the heart shapedcam groove is defined on the battery carrier and the cam follower isattached to the housing.
 33. The electronic device of claim 29,comprising a spring engaged with the battery carrier that biases thebattery carrier toward the open position.
 34. The electronic device ofclaim 29, wherein the battery carrier is pivotally connected to thehousing for pivoting movement relative to the housing between the closedposition and the open position.
 35. The electronic device of claim 29,further comprising structure connected to the housing that is configuredto prevent closure of the battery carrier from the open position if abattery is incorrectly installed in the battery carrier.
 36. Theelectronic device of claim 29, further comprising a lockout mechanismthat is configured to prevent closure of the battery carrier, when thebattery carrier is at the open position, without a battery installed inthe battery carrier.
 37. The electronic device of claim 29, furthercomprising a tamper resist mechanism that is configured to prevent thebattery carrier from being opened when the battery carrier is at theclosed position.